shifting issue

[tepidarium]

Hi all -

Assuming parts are compatible i.e. no spacing issues between a freewheel and shifters, and assuming that the chain is the right length...

What could be the possible cause for shifting problems between cogs?

 

[meehs]

Kinda vague.... Possible causes?

• Cable tension not set properly
• Derailleur "travel limit" screws not adjusted properly
• Dirty and/or corroded cable/housing
• Cable not seated properly in shifter or not anchored properly in derailleur
• Derailleur cage is bent
• Derailleur hanger is bent
• Shifter is worn-out, damaged, gucked-up or otherwise not functioning properly
• Short piece of cable housing that runs from chainstay to derailleur is TOO short
• Cable housing isn't seated properly in one or more of the cable stops on the frame
• Operator error

In other words there are a lot of things that might be screwing-up your shifting. I'm sure there are mor ethat I missed. You can start by checking those things anyway. Good luck!

 

[tepidarium]

Hiya,

Yeah I know it was vague…. really because I'm not sure what's going on w/my bike...this extends back to the thread about converting downtube shifting 7 speed campy bike to ergo. Basically, long story short -
I got New Old stock Campy 8 spd shifters but they didn't work with my 7 speed campy freewheel - my LBS told me I needed a Sachs 8 speed freewheel - so I found a 12-28 New Old Stock one. He put the freewheel on the bike, adjusted the axle, put on a new chain.

Now, unfortunately, the bike has a problem shifting to the larger cogs...my LBS is baffled. He thinks it may be the rear-derailleur...but he is not sure. He is going to try another derailleur to see...

Also, he had to use tandem cables on my bike because the stem - Nitto Technomic is setup up really high on my 63cm bike.

So, basically that's the sad story.

 

[mjw_byrne]

Could it be that the large cogs are a little too large for the derailleur? This problem might be rectified by adjusting the screw at the point where the derailleur mounts to the frame - it rotates the whole mech around to increase the distance between the top jockey wheel and the sprockets.

 

[dhk]

The downside of indexed shifting is that everything has to be compatible in order for the derailleur to click into just the right position at every shift. Doesn't the Campy Ergo shifting require a Campy 8 sp cassette? The index shifters are set up for a specific cog spacing; are you sure the Sachs freewheel has the same spacings as Campy?

I'd assume the Campy 8 sp ergo levers require an 8 sp Campy cassette and a compatible derailleur to work properly.

 

[tepidarium]

Originally posted by dhk
The downside of indexed shifting is that everything has to be compatible in order for the derailleur to click into just the right position at every shift. Doesn't the Campy Ergo shifting require a Campy 8 sp cassette? The index shifters are set up for a specific cog spacing; are you sure the Sachs freewheel has the same spacings as Campy?

I'd assume the Campy 8 sp ergo levers require an 8 sp Campy cassette and a compatible derailleur to work properly.

I have been assured by my LBS that the sachs freewheel is compatible with the campy shifters. That's why he wanted me to get the freewheel even though it was hard to find as it is not made anymore.

Initially, the concensus was that campy spacing on the 7 speed freewheel was the same s an 8 speed freewheel and all I needed were 8 speed ergo shifters which turned out not to be the case...